This invention relates to accessing a private network.
Small office/home office (SOHO) and residential computers may permanently connect to external networks such as the Internet via broadband connections. The computers within a SOHO or a residential environment can be connected together by private networks to share resources including the broadband connection. A private network can be connected to the broadband connection via a gateway device such as a personal computer running gateway software or a special purpose gateway device.
Such gateways can use Network Address Translation (NAT) to map connections from within the private network to connections outside the network to the Internet. NAT allows the private network to set up one set of Internet Protocol (IP) addresses for use on the private network and another set of IP addresses for use on the Internet. With NAT using different IP addresses inside and outside the private network, networked devices outside the private network may have difficulty connecting to the private network using proper addressing.
The IP addresses for use on the private network are reserved IP addresses set aside for use on the private network and are not valid routable IP addresses on the Internet. If one of these reserved IP addresses appeared in a packet at an Internet-based router, the router would drop the packet.
Further, the broadband connection may be provided by an Internet Service Provider (ISP) that prevents or hinders devices on the Internet from connecting to the private network. The ISP may dynamically assign an IP address to a contact point within the private network, such as the gateway device, rather than allocate persistent IP addresses to the devices within the private network. Without a persistent IP address being assigned to the gateway device, devices on the Internet may have difficulty locating, and therefore accessing, the private network at the proper Internet IP address.